**2.13 Atomic absorption spectroscopy**

Atomic absorption spectroscopy is a common method to detect metals and metalloids in liquid samples. Free atoms of gas are generated in the atomizer and they can absorb the radiation at a given frequency. By atomic absorption, the absorption of ground-state atoms in the gaseous state can be measured. The atoms make transitions to higher energy levels by absorbing the UV or visible light. The concentrations of metals or metalloids are determined from the absorption amount. To measure calcium content of the wine samples with an analytical method, atomic absorption unit (Jarrell Ash) was used at Middle East Technical University, Chemical Engineering Department.
